Well drill



June 14, 1932. J. c. WRIGHT ET AL Filed Aug. v25. 1927 Patented June 14, 1932 UNITED STATESv PATENT o1-'FICE i' :Essa c. WRIGHT, o

HUNTINGTON' IARK, AN'D LYNN F. BON'NEY, 0F LOS ANGELES,

GAIJIORNIA, AS IGNORS, BY MESNE ASSIGNMENTS, T GLOBE OIL TOOLS COM- PANY, 0F LOS NIETOS, CALIFORNIA., A CURPORATION 0F CALIFORNIA WELL DRILL application mea august as, 1927. semi m. 214,964.

This invention has to do with a well drill and has particular reference to a drill or bit for use in drilling wells with the rotary method. It is a general object of this invention to provide an effective, eiicient and improved device of this character.

It is a general object of this invention to rovide a bit which operates to cut by stages,

or instance, by making an initial cut to leave V a core and then cutting away the core.

l It is another object of this invention to provide a bit including two cooperating cutting means one operable to make an annular cut, the other operable to out away the center or core left by the one iirst mentioned means.

A further object of this invention is to provide a bit having a body of improved formation-wherein an annular end part is sup-y ported through a plurality of spaced' legs.

The various ob3ects and features of the'invention will be best and more fully understood from the following detailed description of a typical form and application of the invention throu hout which description we will refer to t e accompanying drawing in which Fig. 1 is a side elevation of the bit, Fig. 2 is a transverse sectional View of the bit being a view taken as indicated by line 2 2 on Fig. 1. Fi 3 is a detailed sectional view taken as in icated by line 3 3 on Fig. 2. Fig. 4 is a detailed sectional view taken as indicated by line 4 4 on Fig. 2 and Fig. 5` is adetailed sectional view taken as indicated by line 5 5 on Fig. 1.

The bit includes, generallysa body 10, outer cutter cutting means 11 carried lby the body to mak e an annular, cut in the formation being drilled, inner cutting mea-ns 12 carried he vbody operable to remove or cut away the centeror core left by the outer cutting means 11, and various other parts and `features, the details of which will be hereinafter described.

5 The. body 10 is provided at its upper end.

with a central vertically disposed shank 13, 1at

its lower end with an annular end part 14, and has a plurality of spaced legs 15 conl necti'ng the shank 13 to the annular end part 14. The shank 13 is provided at its upper end 60 with a tapered screw threaded pin projecp tion 16 whereby the bit can'be attached to a strino' of drilling tools, for instance, a string vof drill pipe.

The annular end part 14 ofA the' bit is pro- 65 vided as a carrier or mounting for the outer cutting means 11. The outside diameter of the annular end part 14 is somewhat less than the diameter of the hole to be drilled and in practice the inside diameter is made as large as possible leaving the ring suiciently thick to properly support the cutting means 11. Likewise the length or vertical dimension of the annular end part 14 is made such as to give this part the proper body and strength to withstand the strains to which it is subjected.

The legs 15 proyided to connect the shank 13 and the annular end' part 14 may vary in number, arrangement and proportions. In

ractice, the bit may be provi ed with two egs 15 spaced 180 degrees apart and proportioned substantially as shown throughout thev drawing. The annular endpart 14 is larger in diameter than the shank 13 and, therefore, the legs 15 extend outwardly and downwardly from the lower end of the shank 13 to 'oin the upper end of the end part 14. In p actice, the various parts of the body, for instance, the shank 13, legs 15 and part 14, may 80 be forged or otherwise formed integrally or they may be formed separately and suitably joined or connected. In the drawing we have shown the legs 15 integral with the shank 13y and have shown-the' annular end part 14 attached to the lower ends of the legs 15. In this particular case, the lower ends 16 of the legs extend into recesses 17 provided in the end art 14 and in ractice the joinin parts of t e legs .and en part 14 are wel ed togetherfto make a solid connection in which the plarts are practically integral. T e outer cutting means 11 carried by the annular end part 14 of the body may, as far,

as the broader principles of the invention are concerned, be of any type or formation operable to make an annular cut in the formation being drilled. In the drawing we have we have shown four cutters 18 carried by the annular end part 14, each cutter being provided with asharpened lower edge 20 and a sharpened outer side edge 21.v The cutters 18 seat in upwardly converging sockets 22 provided in the lower end of the part 14 and have upwardly extending shanks 23 that project upwardly through vertical openings 24 in the part 14 to project above the part 14. Retaining nuts 25 are screw threaded tof the upper ends of the shanks23 to hold the cutters tightly in place. The cutters 19 ofithe means 11 may be similar generally to the cutters 18 except that they project inward radially from the end part 14 instead of outwardf ly. The cutters 19 project downwardly from the lower end of the annular end part 14 and are provided with lower cutting edges 26 and inner side cutting edges 27. Wehave shown two cutters 19 arranged 180 degrees apart.

. Further, in the arrangement shown in the drawing, the. cutters 19 are shorter than the `cutters 18 and, therefore, -do Anot project downwardly from the lower end of the part 14 as far as the cutters 18. The cutters 19 maybe mounted and retained in part 14 in the same manner as are the cutters`18. The cutting means 11 just described, being carried bythe annular lower end part 14 of the body, operates to make an annular cut in the formation being drilled. that is in the bottom of the hole being drilled. leaving a center or core that passes upwardly through the part 14 as the .bit advances.

The inner cutting mea'ns 12 is provided by our invention to remove the core left standing by the outer cutting means 11. In the form of the invention illustrated in the drawlng the inner cutting means 12 includes -two blade cutters 30 mounted 'on they inner sides of the legs 15. The blades 30 are carried by the legs 15 softhat they are-diametrically opposite each. other and extend u wardly and inwardlyl to be inl an inverted lyformation. The blades 30 shown in the drawing ing horizontally disposed cutting edges 33.

Further lin the pre erred arrangement the two blades 30 are stepped, as just described,

so that opposite or corresponding vertical cutting edges 32 are dierent distances from the vertical center of the tool while the horizontal cutting edges of the two blades occur at different points vertically of the tool.

With this formation of cutters 30, which is clearly shown in Fig. 1 of the drawing, the

top or upper end of the core as it passes up` 80 wardly in the bit is cut or trimmed away. It is to be-noted that the spaces between the legs 15 leave ample room or clearance for the discharge of cuttings made by the blades 30.

In the construction illustrated in the drawing blade holders 40 are secured to the inner sides of the legs 15. The inner parts of the blades are recessed into the holders and suit-1 able bolts 41 are provided to retain the blades in the holders. It will be obvious, however, 9

that any suitable construction may be employed in mounting the blades in the proper manner between the legs 15, In accordance with our invention provlsion is made for directing circulation iluid,

for Ainstance mud laden Huid, to the cutting parts to keep the cuttings washed away and to prevent the undesirable accumulation of mud or cuttings on the various parts of the tool. drawing the fluid passage 50 extends downwardly through the pin 16 and shank 13 to conduct circulating Huid from the string of drill pipe carrying the bit to distributing .conduits or pipes 51 and 52. The distribut- 105 ing pipes 51 conduct the circulating fluid from the openings 50 to openings' 54 in the annular lower end part 14. The openings 54 discharged downwardly immediately ahead of the cutters of the means 11, keeping the cutlters clean and keeping the hole properly flushed during operation of the bit. Pipes 51 may in practice be arrangedfadjacent the legs 15 so that they are held and protected by the legs. lThe pipe or 'pipes 52 receive 115 circulating liuid from the opening 50 and direct it downwardly at the upper ends of the blades 30 to Hush the blades during theoperation of the bit.

From .the foregoing description of thel20 structural features of the bit it is believed that its action or mode of operation will be readily understood. However, we Wish to particularly point outa few of the salient `features which are peculiar to our invention.

The bit when in operation makes a comparatively narrow annular cut into the formation or into the bottom of the hole being drilled leaving a comparatively large core to extend upwardly into the bit to bev destroyed or re- 130 In the construction illustrated in the 100 l or be cut away.

Vmum amount of cutting or drilling is done into solid formation. The outer cutting means 11- make this initial cut into the solid formation. However, because of the fact that 'I the cut made is comparatively narrow, the

cutting'edges are comparatively short and even though dulled are eiiectivein penetrating or entering the formation. The inner cutting means 12 operates on l the unconfined formation, that is, upon the corewhich stands in the bottom of the hole or projects into the bit. This core, because of the manner in which it projects upwardly from the bottom of the hole, has no side support and is, therefore, easily removed or drilled away by the `means 12. Further, the ample clearance around the core at or opposite'the cutting means 12 allows the core to freely break down The bit provided by our invention has another noteworthy feature distinguishingy it from other drilling tools, that is, it tends to maintain or to drill a straight hole. An ordinary pilot or central cutting bit, upon engaging or drilling into a hard inclined formation, is deflected more or less by the formation with the result that the hole drilled is crooked or out of line. With our bit the annular or outer cutting means 11, being of comparatively large diameter and in making a comparatively narrow cut, enters or drills into and through an inclined formation with little or no tendency to become deflected. Further, the cutting means 12 in acting on the c ore has little or no influence onthe direction of feed of the bit as the core cuts away with comparatively little resistance. Further in this connection, the annular end part 14 of the body, in surrounding the core left by the outer cutting means 11, is held or guided more or less by the core, -thus further -tending to maintain the bit central or straight.

Having described only a typical preferred form of our invention we do not wish to'limitl formation for the purpose of destroying the Y core cut by said first mentioned cutters, each of said secondary cutters comprising a at plate havinga series of step ed cutter portions on one edge thereof an means for at-A taching said secondary cutters to said leg members.

In witness that we claim the foregoing we have hereunto subscribed our names this 15th day of August, 1927. f

v JESSE C. v WRIGHT.

v DYNN F. BONNEY.

loo

ourselves to the specific details set forth, but

Vwithin said leg members and arranged in V- 

